Thread: Need Help Converting Audio 44.1KHz LPCM flac to 48KHz LPCM + Add to DVD

[nagysaudio]

Ok, I have quite a project and I definitely need all the help I can get. I'm pretty new to this, so I would truly appreciate if you guys could walk me through step by step and recommend what programs to use. Currently, I have Sony Sound Forge (http://www.videohelp.com/tools/Sound_Forge) 9 and Sony Vegas (http://www.videohelp.com/tools/Vegas) 9 Pro.

Here's my project...

I want to take a studio production DVD of The Terminator and replace its audio entirely. The Terminator DVD has a 5.1 Dolby Digital mix as well as an original mono recording. I would like to replace this mono recording with a new mono soundtrack. Or, if possible, just add the new mono soundtrack in addition, so the DVD will now have 3 audio options, 5.1 Dolby Digital, original mono, and my new mono.

My new mono recording is in two pieces (two files). Both files are 44.1KHz LPCM flac. These flac files have been taken from the THX laser disc of The Terminator. I'm doing this because The Terminator happens to be my favorite movie of all time and I cannot stand the poor quality of the original mono track on the DVD and I despise the 5.1 Dolby Digital track because it has been completely changed and butchered. The recording from the laser disc is fantastic, so I would love to use that.

I need much guidance in how to go about converting the 44.1KHz LPCM flac files, to a 48KHz LPCM file. Then syncing this new file with the original DVD and making a new copy of the movie. What are my options here? Can I remove the original mono track on the DVD and replace it with my new one? Or can I just add a third audio option? I don't want to mess with the original DVD video as to not degrade it. All I want is to either add a new audio track, or replace the existing mono one.

How do I go about syncing this new sound to the original DVD's video?

And How do I convert the 44.1KHz LPCM flac files to a 48KHz LPCM file. As I understand, DVD calls for a 48KHz spec.

Could someone walk me through this entire process from the beginning to end, step by step? I know it's tedious, but I would appreciate it greatly.

Thank you so much for all the help!

[Blue_MiSfit]

44.1 KHz FLAC to 48 KHz PCM WAV: Use eac3to!


eac3to input.flac output.wav -resampleto48000


Sync can be a little tricky. Here's what I would suggest:
1) Use the code above as a starting place
2) Use MKVMergeGUI to mux your MPEG-2 video with this new PCM track
3) Open this in VLC, and use the sync adjust function to figure out what the proper sync offset is
4) Start again with eac3to using the original FLAC source, and add "+5000ms" or "-5000ms" without quotes (as an example for adding or subtracting 5 seconds of delay to the audio track) to the command line. This will output a new WAV file that will have the delay applied, so you can mux with your MPEG-2 video straight away and not have to mess with sync on playback

Derek

[Ghitulescu]

If this is the digital sound of the laserdisk then yes you have to convert it. There are several alternatives, practically all sound processors have such a function (resampling). A freeware CLI is sox (extremely good).

If the sound is analog, then you can recapture it at 48kHz and that's it ;).

I see you have Sound Forge. I worked long time ago with it. So practically use the multi track option of soundforge and place both files using either the mono or the 5.1 track from the DVD as a place holder (to help you synch the LD audio). Then move the new file left and right so that they "synchronously beat" with the audio from the DVD (the placeholder). Which LD audio do you use, mono or 5.1 plays here no role, it serves you only to synch the FLAC.

Let's assume both versions (LD vs. DVD) are the same, no cuts, no extra scenes, same fps. In this case you don't have to worry about nothing, just export the synched track as one file, convert it to AC-3 or leave it as LPCM, and reauthor the DVD. There are plenty of guides here or google may be your friend (reauthoring can be simple or complicated, depending on what do you want, this is why I direct you to seach). Should the versions be different than you have either to cut parts from the LD audio or to "patch" the sound with parts from the DVD (yes, I know, but bad sound is better than no sound ;)). Or even to stretch the audio (like PAL <-> NTSC conversions).

[ramicio]

You gotta be sure the movies have the same cuts in all the same places between the 2 versions. Most likely not. What is butchered about the sound? The mono track was probably made to play back through crappy 80s TV speakers. The 5.1 is made for a surround system. Not better or worse, just different. Are there no stereo mixes on the disc? I have no idea what equipment you are playing this on, but there are my 2 cents. I was obsessed with the movie Speed Zone. VERY low budget, and the studio is not around anymore. It never went to DVD, and finding a good VHS copy is impossible. I found a bootlet DVD, still wasn't acceptable to me and still only 4:3, so it was just a VHS cap. There is obviously archives of it somewhere, as studios don't just disappear, they get bought out. I wish they would scan the film and put it on Blu-ray. But life goes on and I got over it.